Pseudo-nitzschia seriata (Cleve) Peragallo
Pseudo-nitzschia seriata is a pennate diatom with the potential to produce domoic acid, the causative toxin in amnesic shellfish poisoning and domoic acid poisoning (Lundholm et al. 1994).
Pseudo-nitzschia seriata has caused domoic acid contamination of shellfish in Atlantic Canada and toxic forms are present around Europe.
Can be difficult to distinguish from Pseudo-nitzschia australis.
In P. seriata, cultures exposed to a long photoperiod (18:8 L:D) had higher total toxin production than those exposed to a short photoperiod (9:15 L:D) (Fehling et al. 2005). Isolates from western Scottish waters grew well in the laboratory at 15 degrees Celsius and produced 0.16 to 0.23 pg of domoic acid per cell in stationary phase (day 25 of batch culture growth)(Fehling et al. 2004). Another study using western Scottish isolates tested differences between phosphate and silicate limited cultures. Phosphate limited cultures produced low levels of domoic acid in exponential growth phase. Most domoic acid was produced in the immediate post exponential phase with little produced during cell senescence. stationary phase. Exponential growth stopped after P was reduced to low concentrations. Then the culture entered stationary growth phase. Silicate limited cultures produced more domoic acid. Exponential growth was fast and followed by a period of slower growth until Si was exhausted. Then the cell density rapidly decreased and showed a second period of active metabolism probably fueled by regenerated Si. This was the period of highest domoic acid production (Fehling et al. 2004). A Canadian isolate of P. seriata had a maximum specific growth rate of 0.65 ± 0.03 per day and a maximum pH for growth of 9.0 in the laboratory (100 micromolar photons m-2 s-1 and 15 deg C; Lundholm et al. 2004).
The average cell volume of a Canadian isolate was 1105 ± 50 cubic microns (Lundholm et al. 2004).
Pseudo-nitzschia seriata has only been reported from the Northern Hemisphere. It is abundant on the west coast of the United States in the autumn (Fryxell et al. 1997). In the Skagerrak, it is common in the winter and spring with greatest abundances in spring (Hasle et al. 1996). It has been documented in the Chesapeake Bay (Marshall et al. 2005). From Hasle 2002: Atlantic: north of Svalbard, ca 80°N (Quillfeldt von, 1996) to Grand Banks south of New Foundland, ca 45°N ( Hasle, 1972), including Barents Sea, west and north of Svalbard ( Quillfeldt von, 1996), Norwegian coastal waters ( Hasle and Hasle), Norwegian Sea ( Hasle, 1965), Icelandic (unpublished observations), Danish ( Lundholm et al., 1994), Scottish ( Gallacher et al., 2001) and Irish ( Cusack et al., 2000) waters, North Sea and Kiel Bay, Baltic ( Hasle, 1972), English Channel (unpublished observations), eastern Atlantic (unpublished observations); west coast of Greenland and Resolute Bay, Canadian Arctic ( Quillfeldt von, 1996), Hudson Strait ( Hasle, 1965), Gulf of St. Lawrence ( Bérard-Therriault et al., 1999), western Atlantic (unpublished observations), edge of continental shelf, east coast of US (Hargraves, personal communication). Pacific: none.
P. seriata abundance is negatively correlated with total fluorescence in the Bay of Fundy, Canada (Kaczmarska et al. 2007).